Produit Nom:Metsulfuron-methyl 95%TC

CAS No.: 74223-64-6

Description: 

Metsulfuron-methyl

Herbicide

HRAC  B WSSA  2; sulfonylurea

NOMENCLATURE

Chemical Abstracts name methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]benzoate 

CAS RN [74223-64-6]

PHYSICAL CHEMISTRY

Mol. wt. 381.4

M.f. C14H15N5O6S

Form Colourless crystals; (tech., off-white solid, with a faint ester-like odour).

M.p. 158 ºC

V.p. 3.3 ´ 10-7 mPa (25 ºC)

KOW logP = -1.74 (pH 7)

Henry 2.3 ´ 10-10 Pa m3 mol-1 (calc.)

S.g./density 1.47

Solubility In water 0.55 (pH 5), 2.79 (pH 7), 213 (pH 9) (all in g/l, 25 ºC). In hexane 0.00079, xylene 0.58, ethanol 2.3, methanol 7.3, acetone 36, dichloromethane 121 (all in g/l, 20 ºC).

Stability Stable in air up to c. 140 ºC. Hydrolysis DT50 (25 °C), 22 d (pH 5), stable (pH 7 and 9).

pKa 3.3 

APPLICATIONS

Biochemistry Branched chain amino acid synthesis (ALS or AHAS) inhibitor. Acts by inhibiting biosynthesis of the essential amino acids valine and isoleucine, hence stopping cell division and plant growth. Selectivity derives from rapid metabolism in the crop. Metabolic basis of selectivity in sulfonylureas reviewed (M. K. Koeppe & H. M. Brown, Agro-Food-Industry, 6, 9-14 (1995)).

Mode of action Selective systemic herbicide absorbed through the roots and foliage, with rapid translocation both acropetally and basipetally. Susceptible plants cease growth almost immediately after post-emergence treatment, and are killed in 7-21 days. Surfactants increase the activity of metsulfuron-methyl on certain broad-leaved weeds.

Uses Metsulfuron-methyl controls a wide range of annual and perennial broad-leaved weeds in wheat, barley, rice and oats, by either pre- or post-emergence application, at 4-7.5 g/ha post-emergence.